This invention relates to connectors for use in fiber optic communication systems.
In a fiber optic telecommunication or data communication system optical fibers serve to carry pulse coded optical signals from a transmitter station, perhaps to one or more repeater stations, and then to a receiver station. Whether for the purpose of connecting fibers end-to-end in a long haul system or of splicing together fibers broken by environmental elements or otherwise, it has long been recognized that some form of optical connector would be required to make accurately aligned connections between pairs of single fibers or between pairs of fiber arrays or ribbons.
Two of the predominant optical connectors for pairs of single fibers are the biconic connector described by P. K. Runge in copending application Ser. No. 630,930 filed on Nov. 11, 1975 and the nested rod connector of A. W. Warner, Jr. in copending application Ser. No. 754,603 filed on Dec. 27, 1976 (now U.S. Pat. No. 4,009,832), both of which are assigned to the assignee hereof. On the other hand, connecting ribbons of fibers in a fiber cable, for example, can be accomplished in a number of ways, but one of the more elegant, yet simple, utilizes parallel V-grooves etched in a semiconductor wafer as described by C. M. Miller in U.S. Pat. No. 3,984,172 issued on Oct. 5, 1975 and also assigned to the assignee hereof.
Despite all of the activity in the optical connector art, little attention, if any, has been given to making connections at opto-electronic interfaces (e.g., transmitters, repeaters and receivers) where both optical and electronic connections are required. And, notwithstanding that the relatively new optical connector art has borrowed heavily from the more mature electrical connector art, the need for a device capable of making simultaneous optical and electrical interconnections remains unsatisfied. This type of connector might find application, for example, in an electronic switching system (ESS) in which fiber optic data links may be used to interconnect different electronic equipments. In the No. 4 ESS manufactured by Western Electric Company such data links have been proposed to interconnect time slot interchangers with voice interface frames, time multiplexed switches and clock circuits, and to interconnect peripheral unit buses with the No. 1A processor and the time multiplexed switches.
These fiber optic data links are being given serious consideration as replacements for coaxial cable links for a number of reasons: optical signals offer wider bandwidth and are immune to electromagnetic interference; and fiber optic interconnections electrically isolate the interconnected equipment on different frames, and reduce the cable congestion on frames. But, in order to realize these advantages in a cost effective way, more than one data link should be included on each opto-electronic interface; i.e., on each circuit pack which includes the electronics necessary for driving optical transmitters or detecting optical data. This implies the need to interconnect arrays of individual optical fibers. In addition, from the standpoint of serviceability, it is desirable that maintenance personnel be able to remove readily the circuit packs in order, for example, to replace defective ones or to rearrange connections as the system usage expands.